Drilling apparatus



R. A. M CALLUM DRILLING APPARATUS Filed Oct. 16, 1944 Ewen/far.- RobertQWJcLalZum.

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Patented May 15, 1951 DRILLING APPARATUS Robert Anthony McCallum, Michigan City, Ind.,

assignor to Joy Manufacturing Company, a corporation of Pennsylvania Application October 16, 1944, Serial No. 558,849

8 Claims. 1

This invention relates to a drilling apparatus, and more particularly to improved means for supplying drilling fluid to the drill bit of a rotary drilling apparatus particularly intended for earth boring.

In drilling apparatus of the rotary type, it is the usual practice to extend the drill rod or drill stem axially through the feed screw or drill spindle and to attach the water swivel to the upper end of the drill rod or stem. Such an arrangement necessitates the use of a long drill rod or stem section extending completely through the feed screw or spindle. According to the present invention, I provide a sealing plug slidabl arranged in the feed screw or spindle and engaging the upper end of the drill rod which extends into the feed screw or spindle, whereby it is possible to eliminate such a long length of drill rod or stem while an adequate water seal between the feed screw or spindle and drill rod is maintained regardless of the position of the rod in the spindle. To assure proper seating of the sealing plug on the upper end of the drill rod, there is provided means for causing a differential in pressure between the opposite ends of the sealing plug; and this means is illustrated, though it may obviously assume other forms, as a spring loaded valve carried by the plug, past which the water flows to the drill rod so that a sufiicient excess pressure at the upper side of the plug is obtained to assure seating of the plug against the rod. The spring load on the valve is comparatively light so that there is a substantially free flow of water past the seal. To insure adequate sealing the effective area on the sealing plug subjected to the pressure in the rod line may be substantially reduced, as compared with the area on the plug tending to press the latter towards the rod line. While a feed screw is provided'to feed the drill rod, it will be evident that the same may be fed in other well known manners.

An object of the present invention is to provide an improved drilling apparatus. Another object is to provide an improved rotar drilling apparatus having improved means for conducting drilling fluid to the drill bit. A further object is to provide an improved seal between a pair of telescopically arranged fluid conduits. A still further object is to provide an improved liquid seal between the drill spindle and the drill rod of a rotary drilling apparatus. Yet another object is to provide an improved liquid seal embodying a suitably loaded valve so that a sufficient excess in pressure is provided at the upper side of the seal to assure seating of the seal, by the pressure of the which the drill rod is rotated. A still further object is to provide an improved sealing plug disposed in the hollow feed screw of a drilling apparatus and held in engagement with the upper end of the drill rod by the pressure of the liquid to prevent leakage of the liquid past the exterior of the drill rod. Another object is to provide an improved slidable sealing plug having improved valve means associated therewith. Still a further object of the invention is to provide an improved seal for a rod line effective irrespective of the position of the latter in the associated drill spindle. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention ma assume in practice.

In this drawing:

Fig. 1 is an elevational view of a drilling apparatus with which an illustrative form of the invention is associated.

Fig. 2 is a vertical sectional view through the drill rod chuck, showing the improved seal in operative position.

Fig. 3 is a cross sectional View taken on line 3 3 of Fig. 2.

In this illustrative embodiment of the invention, there is shown a rotary drilling apparatus, generally designated l with which the improved water seal, generally designated 2, is associated. The drilling apparatus may be generally, similar to that disclosed in my copending application, Ser. No. 558,848, filed concurrently herewith, although it will be apprecated that the invention may be embodied in drilling apparatus of other types.

The drilling apparatus herein comprises a casing 3 mounted on a suitable support and carrying a, motor 4. The motor is operatively connected to a drive sleeve arranged within the casing and splined to a tubular spindle 5, and the latter, in this instance, has external screw threads 6 to provide a feed screw which engages a rotatable feed nut likewise arranged within the casing 3 and driven by the motor. The lower end of the spindle carries a conventional jaw clutch I for securing a hollow drill rod 8 to the spindle for rotation and axial movement therewith. The spindle is hollow, and the drill rod projects into the spindle in the manner shown in Fig. 2. The

chuck jaws are designated 9 and may be adjusted by screws Ill in a well known manner. While the spindle is fed by means of screw threads and a feed nut, it will be evident that the spindle may be fed in various well known manners. Since the drill structure above described is clearly disclosed in the copending application above referred to, additional illustration and description thereof are herein unnecessary.

Attached at ll to the upper end of the spindle is a conventional water swivel I2 through which water may be supplied to the interior of the spindle from a suitable supply hose l3. This permits relative rotation between the supply hose and the spindle, while preventing leakage. The drill rod projects through the chuck i into the hollow spindle so that water supplied to the hollow interior of the spindle may flow into the bore of the drill rod and thence to the drill bit to clear away the cuttings at the bottom of the hole.

'The improved water seal 2 is in the form of a cylindrical plug l4 slidabl mounted in the bore of the spindle, so that it may effect sealing irrespective of the relative position of the drill rod and spindle, and is held against the upper end of the drill rod by the pressure of the circulating water in the spindle. It is a close enough fit in the spindle bore to prevent leakage. Desirably the plug will have a flexible upper lip or edge to promote sealin and the entire plug may be made of rubber or a synthetic compound, if desired. The sealing plu is desirably cup haped in form and has a transverse partition [5 perforated by openings I 6. Below the partition i a chamber I! connected by a reduced axial bore l8 to the bottom of the plug. A valve i9 is held seated against a seat 20 at the bottom of the bore l8 by a coil spring 2|. This coil spring is arranged between a nut 22 threaded on the upper end of the valve stem 23 and the upper surface of the partition 15. The spring constantly urges the valve towards closed position against its seat. The pressure of circulating water in the spindle opens the valve to permit flow of water to the drill rod, and the valve is sufficiently loaded by the spring so that an adequate excess of pressure is provided at the upper side of the p u to insure the plugs moving in the spindle against the upper end of the drill rod. The upper end of the drill rod section 8 is beveled at 24 to insure more effective seating and sealing with the bottom surface of the plug l4, and the area at the lower side of the plug subjected to the pressure of the liquid in the rod line is smaller than the area on which the fluid acts inside the spindle, to press the plug towards the rod. The eifective area subjected to liquid pressure at the upper side of the plug when the latter is seated is thus sufficiently greater than the effective area at the lower side to hold the plug seated against the drill rod against any ordinary back pressures in the rod. Thus leakage of the water along the exterior of the drill rod and out past the chuck is substantially prevented. It will be understood that while the spring tension is enough to insure seating of the plug against the rod and aids somewhat in the provision of sealing pressure, the differential in area is the source of the primary seal-effecting force.

As a result of this invention an improved means is provided for conducting drilling fluid to the drill bit of a drilling apparatus in an improved manner. By the provision of the improved sealing plug between the spindle and the drill rod, it is possible to attach the water swivel directly to the upper end of the drill spindle. The spring loaded valve carried by the plug assures suflicient pressure at the upper side of the plug so that seating of the plug against the upper end of the drill rod is assured regardless of the relative position of the latter in the spindle. The differential areas, supplemented in some manner also by the differential in pressure, maintains an effective seal. Other uses and advantages of the invention will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a drilling apparatus, a hollow drill spindle, a water swivel attached to one end of the spindle for conducting water to the interior of the spindle, a rod chuck carried by the spindle for securing a hollow drill-rotating rod to the other end of the spindle, a hollow drill-rotating rod extending through the chuck into the spindle and adapted by said chuck to be secured to said spindle in axially different positions relative to the latter, and a sealing plug freely slidable within said hollow drill spindle and held'by the pressure of the water in sealing engagement with the inner end of the drill-rotating rod regardless of the relative axial position of the latter to said spindle, said plug having an opening therethrough the end of which towards said hollow drill-ro tating rod is completely within the area circumscribed by the wall of the latter and said plug having a portion thereof constituting such a fit for the bore of said hollow drill spindle as to prevent liquid flow past the periphery of said plug through said bore.

2. In a drilling apparatus, a hollow drill spindle, a water swivel attached to one end of the spindle for conducting water to the interior of the spindle, a rod chuck carried by the spindle for securing a hollow drill-rotating rod to the other end of the spindle, a hollow drill-rotating rod extending through the chuck into the spindle and adapted by said chuck to be secured to said spindle in axiall different positions relative to the latter, and a sealing plug freely slidable within said hollow drill spindle and held by the pressure of the water in sealing engagement with the inner end of the drill-rotating rod regardless of the relative axial position of the latter to said spindle, said plug having a portion thereof constituting such a fit for the bore of said hollow drill spindle as to prevent liquid flow past the periphery of said plug through said bore, and said plug further having an openin therethrough the end of which towards said hollow drill-rotating rod is completely within the area circumscribed by the wall of the latter, and a valve cooperating with said opening for precluding flow from said rod to rctating rod to the spindle,' a hollow drillro--' tating rod extending through the chuck into the spindle and adapted by said chuck to be secured to said spindle in axially different positions relative to the latter, and a sealing plug freely slidable within said hollow drill spindle and held by the pressure of the water in sealing engagement with the inner end of the drill-rotating rod regardless of the relative axial position of the latter to said spindle, said plug having a portion thereof constitutin such a fit for the bore of said hollow drill spindle as to prevent liquid flow past the periphery of said plug through said bore, and said plug further having an opening there through the end or" which towards said hollow drill-rotating rod is completely within the area circumscribed by the Wall of the latter, and said rod having the portion thereof with which said plug is in sealing engagement of lesser diameter than the internal diameter of said hollow drill spindle whereby a differential in pressure due to the differential in areas subjected to liquid pressure at the opposite ends of said plug is provided for maintaining said plug in sealing relation to said rod.

4. In a drilling apparatus, a hollow drill spindle, a water swivel attached to one end of the spindle for conducting water to the interior of the spindle, a rod chuck carried by the other end of the spindle for securing a hollow drillrotating rod to the spindle, a hollow drillrotating rod extending through the chuck into the spindle and adapted by said chuck to be secured to said spindle in axially different positions relative to the latter, and a sealing plug freely slidable within said hollow drill spindle and held by the pressure of the water in sealing engagement with the inner end of the drill-rotating rod regardless of the relative axial position of the latter to said spindle, said plug having a portion thereof constituting such a fit for the bore of said hollow drill spindle as to prevent liquid flow past the periphery of said plug through said bore, and said plug further having an opening therethrough the end of which towards said hollow drill-rotating rod is completely within the area circumscribed by the wall of the latter, and said rod having the portion thereof with which said plug is in sealing engagement of lesser diameter than the internal diameter of said hollow drill spindle whereby a differential in pressure due to the differential in areas subjected to liquid pressure at the opposite ends of said plug is provided for pressing said plug into sealing relation to said rod and said plug carrying a valve cooperating with said opening through said plug for precluding flow from the rod to the spindle and having a loading spring supported by the plug and imposing on said valve a pressure creating a diiferential in pressure at opposite sides of said plug for pressing said plug into sealing relation to the rod.

5. In an apparatus of the character described, adjustably telescopically arranged relatively larger and smaller fluid conduits, means for releasably securing said conduits together in difierently telescoped relations to each other, a sealing plug slidable freely in the bore of the larger one of said conduits in sealing relation to the latter and sealingly engageable with the end of the other conduit which is inside said larger conduit irrespective of the particular position of the smaller conduit inside the larger one, said plug having an opening extending longitudinally through it, and means for obstructing said opening to produce, during fluid flow through said opening, a difierential between the fluid pressures at the upstream and at the downstream ends, respectively, of said plug.

6. In an apparatus of the character described, adjustably telescopically arranged relatively larger and smaller fluid conduits, means for releasably securing said conduits together in differently telescoped relations to each other, a sealing plug slidable freely in the bore of the larger one of said conduits in sealing relation to the latter and sealingly engageable with the end of the other conduit which is inside said larger conduit irrespective of the particular position of the smaller conduit inside the larger one, said plug having an opening extending longitudinally through the same, and a spring loaded valve mounted on said plug and requiring opening by fluid passing through the opening in said plug in order for fluid to pass from the larger into the smaller of said conduits.

7. A drilling machine, comprising a tubular rotary feed screw, a Working implement coaxial with the feed screw and having a passage therethrough, sealing means in the feed screw to seat against the Working implement having an aperture to register with and convey cleansing fluid into the passage and being subjected to the pressure of such cleansing fluid or pressing said sealing means against the working implement, and means for securing the working implement to the feed screw.

8. A drilling machine, comprising a tubular rotary feed screw, a working implement coaxial with the feed screw and having a passage therethrough, sealing means movable axially of the feed screw for sealing engagement with the end of the working implement having an aperture to convey cleansing fluid to the passage and being subjected to fluid under pressure for maintaining said sealing means in sealing engagement with the working implement, and means for securing the working implement to the feed screw.

ROBERT ANTHONY MCCALLUM.

REFERENCE S CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 885,485 Kellogg Apr. 21, 1908 2,162,743 Norbom June 20, 1939 2,187,371 Cannon Jan. 16, 1940 2,292,674 Terrell et a1 Aug. 11, 1942 2,322,237 Johansen June 22, 1943 

